The significance of the proposed HIV Center for Clinical and Behavioral Studies is multifold: (1) It will contribute to our basic understanding of the actions of HIV on behavior manifestations, including psychiatric disorders (especially depression and anxiety), neurologic changes, cognitive development and functioning and sexual dysfunctions. (2) By carefully assessing at risk behavior for HIV in women, adolescents, IV drug users, and gay men, we will gain new insights in the transmission of HIV infections and in the progression of the disease. (3) This Center will add to our knowledge of the effectiveness of prevention as it is related to different populations at risk, e.g., pregnant women and adolescents. (4) This Center will maximize collaborative efforts of experts of different disciplines and at different hospitals. This will greatly increase the potential for significant results to evolve from interdisciplinary research and ultimately lead to progress in the comprehensive care of patients. (5) This center will strive to work closely with the community and plans an intensive educational input that will reach a wide range of organizations, groups, and individuals.